Universal Personal Telecommunication, is a mobility area that has been defined in standardisation processes since 1989/90.
Universal Personal Telecommunication (UPT) offers a combination of supportive telecommunication services for UPT users. The UPT user has a personal telephone number that the users can keep, throughout his lifetime. If a caller wishes to call a UPT user, instead of having to call a number of places where the caller believes the UPT user might be, the caller can reach the UPT user in a way that the UPT user decides.
This means that instead of having to dial a lot of numbers from a business-card, the caller can dial a universal number to reach the UPT user, a person or a role with UPT number. In the future, it will be possible to use this number to forward all types of traffic, such as voice, facsimile, data and video.
The UPT user can use any terminal to make or receive calls regardless of which telecommunication network or terminal is at his disposal for the moment, for example the Public Switched Telephone Network (PSTN), a business network or a cellular network.
Outgoing calls are charged to the UPT number. Each user can access the available services over a normal Dual Tone Multi Frequency (DTMF) telephone or a DTMF transmitter. Users of UPT are supported by a number of functions that make it possible to store messages, and re-route incoming traffic to various alternative numbers according to the users personal UPT timetable.
In UPT and other personal number type services, the users must update their service profiles with the new locations where they from now on want to receive incoming calls. The new registration number can e.g. be retrieved from the user entered DTMF input or from the call data, i.e. the A-Number or Calling Line Identity (CLI), in these cases the UPT user is relying on that the incoming calls now will be set-up to the registration location. In many situations, this will not be the case:
The user might have entered a wrong number, the network has included a number that can not be used for incoming calls as A-Number e.g. from a public exchange, etc.
The UPT system of today is described in Jonas Sundborg "Universal Personal Telecommunication (UPT)- Concept and Standardisation", Ericsson Review No. 4, 1993, and Soren Wallinder "Implementation of UPT- Universal Personal Telecommunication", Ericsson Review No. 1, 1994.
In the published patent application GB 2 263 845 A, a method of controlling UPT services is described. The method comprises the provision of a subscriber announcement when a UPT subscriber changes his/her Directory Number (DN) in order to notify the subscriber when the UPT number has been changed.